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From Rob Radtke, "I recently ran into some issues trying to save/load a scene graph as a .ive file. The problems came about because the scene graph contained depth textures in it. I have attached a patch (against the current revision: 10919) that fixes the issues that I encountered. Both attachments contain the same patch--one is a .zip file that contains the modified files and the other is a text patch file. Here is a summary of the changes I made:

1) Add getShadowComparison() accessor function to osg::Texture class
2) Modify ReaderWriterTiff::writeTifStream() and _readColor() (in Image.cpp) to handle pixelFormat==GL_DEPTH_COMPONENT as if it were GL_LUMINANCE
3) Modify the Texture classes of the ive and osg plug-ins so that they save/load the following Texture members: _use_shadow_comparison, _shadow_compare_func and _shadow_texture_mode
"